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Any idea how to wire this steam loco

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  • Member since
    November 2009
  • 20 posts
Any idea how to wire this steam loco
Posted by Ron51777 on Thursday, February 14, 2013 1:50 PM

Hi have this 1989 4-6-2 mantua and its HO scale and run's great in dc would like to make it dcc. I opened it up and it looks to be a little more to this one any Idea. also only see one black wire going to front lite there is no back lite and tender had one black wire tender is metal and so is loco frame   Thanks Ron

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Posted by gatrhumpy on Thursday, February 14, 2013 2:06 PM

Someone can correct me if I'm wrong, but I think the metal frame of the locomotive and the tender carry track current.

First, you'll need to take out the motor from the engine and isolate the motor from the frame. Connect the DCC decoder gray wire to the bottom motor contact (after you isolate the motor) and the orange wire from the DCC decoder to the top motor terminal. That will get the motor going.

Not sure about that unit, so you'll have to find out how it gets current from the track. Once you find that out, connect the red wire to the left track pickup and the black wire from the DCC decoder to the right track pickup.

  • Member since
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Posted by N6VC on Thursday, February 14, 2013 2:54 PM

gatrhumpy

Someone can correct me if I'm wrong, but I think the metal frame of the locomotive and the tender carry track current.

First, you'll need to take out the motor from the engine and isolate the motor from the frame. Connect the DCC decoder gray wire to the bottom motor contact (after you isolate the motor) and the orange wire from the DCC decoder to the top motor terminal. That will get the motor going.

Not sure about that unit, so you'll have to find out how it gets current from the track. Once you find that out, connect the red wire to the left track pickup and the black wire from the DCC decoder to the right track pickup.

That's pretty much correct. The caviate is the headlight. It is grounded to the frame. This must be isolated, too. It's a good time to change it to an LED. The old pitman motors are difficult to isolate from the frame. A plastic screw to the motor frame and the rubber mount already there work. The new ones (before they went to China) have a can motor with two leads and operate with less current.  Good time to remotor. I also added wipers to the wheel pickups and changed over to a gearbox drive.

I have 4 of these operating on my layout. One of the three with the Pitman motors will still occassionally cause a short indication, but I haven't found the cause for this, yet.

Jon

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Posted by Train Modeler on Thursday, February 14, 2013 3:18 PM

The middle pic is blurry so I can't say for sure that the tender is picking up on one side and the loco the other.   But a lot of locos from that time period did so.    I would use an ohm meter/continuity checker and trace not only where the current is going, but is it doing so well.   

You can also add electrical pick up by attaching wipers for the drivers.

Richard

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    February 2013
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Posted by N6VC on Thursday, February 14, 2013 3:39 PM

Train Modeler

The middle pic is blurry so I can't say for sure that the tender is picking up on one side and the loco the other.   But a lot of locos from that time period did so.    I would use an ohm meter/continuity checker and trace not only where the current is going, but is it doing so well.   

You can also add electrical pick up by attaching wipers for the drivers.

Richard

and the motor is grounded to the loco frame.

Jon

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Posted by Redvdub1 on Saturday, February 16, 2013 1:04 PM

To isolate the Pittman motors on my Mantua/Bowser locos I just used a laytex caulking material ...I don't think you need to bother with plastic screws to hold the motor down..but it does no harm.  Screws do  help to hold the motor in place while the caulk sets up.  You can then remove them (or not if they are plastic screws). 

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Posted by cjcrescent on Saturday, February 16, 2013 1:26 PM

This is long but the description actually is longer than the actual process. This is the method that I have used on about 20 Mantua locomotives. Haven't had a failure yet.

You don't have to isolate the motor from the frame. All you have to do is isolate the brushes, and thats super easy. At the top of the motor, you'll see whats commonly called the brush holder. Once side is insulated from the motor, and is the black wire to the tender. You can cut off the black wire from the tender.

Take a piece of scrap insulation or shrink tubing, and slide it over the uninsulated side. Both sides should now be insulated, and as a result isolated from the frame.

Install the decoder per instructions. I would also keep as much of the harness as possible to get the decoder mounted in the tender.  I would take the "washer" that is screwed into the tender, and solder it to the black wire off of the decoder. The red pick-up wire can be attached to any part of the loco frame that has a screw that does screw into the frame.

I would use a 16-18 volt bulb as the headlight and solder it to the blue and white wires, leaving enough length to pass thru the boiler. Next part is important! Solder the orange and grey wires directly to the brushes, similar in position that the old wire to the tender was located at. DO NOT SOLDER TO THE MOTOR FRAME!

Test the decoder to make sure the direction as shown on the throttle is correct. If not, switch the orange and grey wire.

Carey

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Posted by richg1998 on Saturday, February 16, 2013 3:26 PM

I have only done two Mantua and the motor was not connected to a brush. How much current does the motor draw at 12 VDC?

Is there is a wire connected from one motor brush to the frame. Cut it. With your ohm meter, check for continuity between the brush and frame. There should be none if the brush is not directly connected to the motor frame.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

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Posted by Ron51777 on Thursday, February 21, 2013 10:15 AM

Hi ya cant seem to get it to work. so called the hobby shop and taking to them to do it. And after they get it done I will open it up and see how to do the other ones I have. Thanks for the help Ron

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